by Daniel Brouse
August 13, 2025
A massive upstream basin of rainwater and snowmelt, dammed by Alaska’s Mendenhall Glacier, began releasing on Tuesday, prompting officials to urge residents in parts of Juneau to evacuate ahead of a potentially dangerous surge of floodwater.
The National Weather Service (NWS) Juneau office issued a flood warning for areas along the Mendenhall River near Auke Bay. The released water from this glacial outburst is flowing downstream, putting riverside homes and properties at immediate risk.
As of Tuesday afternoon local time, river levels were measured at 9.85 feet, with major flooding classified at 14 feet. Officials expect the river to crest Wednesday afternoon at near-record levels of 16.3 to 16.8 feet, setting a new historic high. NWS meteorologist Nicole Ferrin stated, “This will be a new record, based on all of the information that we have.”
The City and Borough of Juneau issued a public advisory confirming that the glacial outburst originated from Suicide Basin. Flooding is expected to continue along Mendenhall Lake and River from late Tuesday through Wednesday. Residents in areas at risk are strongly encouraged to evacuate immediately. A Red Cross shelter is open at Floyd Dryden Gymnasium (3800 Mendenhall Loop Road). Important notices for pet owners: The Red Cross shelter cannot accommodate pets. Evacuated animals should be taken to Juneau Animal Rescue at (907) 789-6997. Safety warning: Do not approach the river. Floodwaters are extremely dangerous, and entering the area endangers both residents and first responders. Stay away from the river to allow safe evacuations and emergency response efforts.
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